The present application relates to a liquid crystal display device and an electronic apparatus, and more particularly, to a liquid crystal display device and an electronic apparatus having measurement portions that are formed on the surfaces of a component substrate and an opposing substrate and are used for measuring a difference between bonding positions of the component substrate and the opposing substrate.
In related art, a liquid crystal display device and an electronic apparatus having measurement portions that are formed on the surfaces of a component substrate and an opposing substrate and are used for measuring a difference between bonding positions of the component substrate and the opposing substrate are known (for example, see JP-A-2000-250021).
In JP-A-2000-250021 described above, a liquid crystal display device including: a TFT-side glass substrate (component substrate); an opposing-side glass substrate (opposing substrate) that is disposed so as to face the TFT-side glass substrate through a liquid crystal layer; an alignment marker (measurement portion) for a TFT substrate-side panel that is formed on the surface of the TFT-side glass substrate; an alignment marker (measurement portion) for an opposing substrate-side panel that is formed on the surface of the opposing-side glass substrate; and a back light that is disposed on a side of the TFT-side glass substrate that is located opposite to the liquid crystal layer is disclosed. In this liquid crystal display device, in a process of bonding the TFT-side glass substrate and the opposing-side glass substrate, the TFT-side glass substrate and the opposing-side glass substrate can be bonded together by overlapping the alignment marker for the TFT substrate-side panel and the alignment marker for the opposing substrate-side panel with each other.
However, in the liquid crystal display device disclosed in JP-A-2000-250021 described above, there is a disadvantage that, for example, when light emitted from the back light is emitted from the TFT-side glass substrate toward the opposing-side glass substrate, the light is shielded in a portion in which the alignment marker is formed, but the light is transmitted through a portion in which the alignment marker is not formed. Accordingly, as the light emitted from the back light is transmitted through the portion in which the alignment marker is not formed, there is a problem in that light leakage occurs from the opposing-side glass substrate side.
Thus, it is desirable to provide a liquid crystal display device and an electronic apparatus capable of suppressing leakage of light emitted from a back light from the opposing substrate side.
According to an embodiment, there is provided a liquid crystal display device including: a component substrate that includes a transistor device; an opposing substrate that is disposed so as to face the component substrate through a liquid crystal layer; a back light that is disposed on a side of the component substrate that is located opposite to the opposing substrate; a first measurement portion that is formed on a surface of the component substrate located on the liquid crystal layer side and is used for measuring a difference between bonding positions of the component substrate and the opposing substrate; a second measurement portion that is formed on a surface of the opposing substrate located on the liquid crystal layer side and is used for measuring a difference between the bonding positions of the component substrate and the opposing substrate; a measurement opening portion that is disposed on the second measurement portion side; and a light shielding layer that is disposed between the component substrate and the second measurement portion and prevents transmission of light emitted from the back light through the measurement opening portion.
According to the liquid crystal display device, as described above, by disposing the light shielding layer between the component substrate and the second measurement portion for preventing transmission of light emitted from the back light through the measurement opening portion, the light emitted from the back light is shielded by the light shielding layer disposed between the component substrate and the second measurement portion. Accordingly, leakage of the light emitted from the back light from the opposing substrate side can be suppressed.
In the above-described liquid crystal display device, it is preferable that the light shielding layer is disposed so as to cover at least an area corresponding to the measurement opening portion in the plan view. In such a configuration, the light emitted from the back light is shielded by the light shielding layer, and accordingly, transmission of the light at least through the measurement opening portion can be prevented. Therefore, leakage of the light emitted from the back light from the measurement opening portion can be reliably suppressed.
In the above-described liquid crystal display device, it is preferable that the first measurement portion and the second measurement portion include a first calibration layer and a second calibration layer, respectively, that have a calibration scale shape used for reading a numeric value, and the light shielding layer is disposed so as to have a shape reflecting a shape of the first calibration layer configuring the first measurement portion on a surface of the first measurement portion that is located on a side opposite to the back light. In such a configuration, the external shape (calibration scale shape) of the light shielding layer in which the shape of the first calibration layer is reflected can be read out. Accordingly, by reading out the external shape (calibration scale shape) of the light shielding layer and the second calibration layer (calibration scale), a difference between the bonding positions of the component substrate and the opposing substrate can be measured.
Preferably, the above-described liquid crystal display device further includes an insulating film that is formed between the first measurement portion and the light shielding layer, wherein the insulating film is formed in a shape reflecting the shape of the first calibration layer that configures the first measurement portion, and the light shielding layer is formed in a shape reflecting a shape of a calibration scale of the insulating film in which the shape of the first calibration layer configuring the first measurement portion is reflected. In such a configuration, also in a case where the insulating film is formed between the first measurement portion and the light shielding layer, the external shape (calibration scale) of the light shielding layer can be read out. Accordingly, by reading out the external shape of the light shielding layer and the second calibration layer, a difference between the bonding positions of the component substrate and the opposing substrate can be measured.
In the above-described liquid crystal display device having the first measurement portion including the first calibration layer and the second measurement portion including the second calibration layer, it is preferable that the first calibration layer and the second calibration layer are formed in a comb-teeth shape in the plan view, the light shielding layer that is formed on the surface of the first calibration layer that is located on a side opposite to the back light is formed in a comb-teeth shape in which the shape of the calibration scale of the first calibration layer is reflected in the plan view, a width of a comb-teeth portion of the light shielding layer is formed to be approximately equal to a width between a comb-teeth portion and a comb-teeth portion of the second calibration layer, and a width of a comb-teeth portion of the first calibration layer is smaller than the width of the comb-teeth portion of the light shielding layer. In such a configuration, by reading out a position on the calibration scale at which the comb-teeth portion of the light shielding layer overlaps without any gap with a space between the comb-teeth portion and the comb-teeth portion of the second calibration layer in the plan view, the amount of deviation of the bonding positions of the component substrate and the opposing substrate can be measured.
In the above-described liquid crystal display device having the first measurement portion including the first calibration layer and the second measurement portion including the second calibration layer, it is preferable that the transistor device includes a gate electrode, a source electrode, and a drain electrode, the first calibration layer is formed from a same metal layer as that of the gate electrode of the transistor device, and the light shielding layer is formed from a same metal layer as that of the source electrode and the drain electrode of the transistor device. In such a configuration, differently from a case where the first calibration layer and the gate electrode of the transistor device are separately formed and a case where the light shielding layer and the source electrode and the drain electrode of the transistor device are formed separately, an increase in the number of manufacturing processes at the time of manufacturing the first calibration layer and the light shielding layer can be suppressed.
In the above-described liquid crystal display device, the light shielding layer is preferably disposed between the component substrate and the first measurement portion so as to prevent transmission of light emitted from the back light through the measurement opening portion. In such a configuration, the light emitted from the back light is shielded by the light shielding layer disposed between the component substrate and the first measurement portion, and accordingly, the transmission of light through the measurement opening portion through the first measurement portion can be suppressed. In addition, by disposing the light shielding layer to the component substrate side relative to the first measurement portion, the first measurement portion and the second measurement portion can be directly visually recognized from the measurement opening portion on the opposing substrate side. Accordingly, the difference between the bonding positions of the component substrate and the opposing substrate can be measured more accurately by using the first measurement portion and the second measurement portion.
In such a case, it is preferable that the first measurement portion and the second measurement portion include a first calibration layer and a second calibration layer, respectively, that have a calibration scale shape used for reading a numeric value, the transistor device includes a gate electrode, a source electrode, and a drain electrode, the first calibration layer is formed from a same metal layer as that of the source electrode and the drain electrode of the transistor device, and the light shielding layer is formed from a same metal layer as that of the gate electrode of the transistor device. By configuring as described above, differently from a case where the first calibration layer and the source electrode and the drain electrode of the transistor device are formed separately and a case where the light shielding layer and the gate electrode of the transistor device are formed separately, an increase in the number of manufacturing processes at the time of manufacturing the first calibration layer and the light shielding layer can be suppressed.
Preferably, the above-described liquid crystal display device includes a black matrix that is disposed on a surface of the opposing substrate that is located on a back light side, wherein the second measurement portion is formed from a same layer as that of the black matrix. In such a configuration, differently from a case where the second measurement portion and the black matrix are separately formed, an increase in the number of manufacturing processes at the time of manufacturing the second calibration layer can be suppressed.
According to another embodiment, there is provided an electronic apparatus including any one of the above-described liquid crystal display devices. According to the above-described electronic apparatus, an electronic apparatus including the liquid crystal display device capable of suppressing leakage of light emitted from the back light from the opposing substrate side can be acquired.